Method and apparatus for testing the productivity of the formation in wells



A. ARMEN-rRouT ET A1. 2,043,225

li- MIITIOD AND APPARATUS FOR `TES'IIING THE PRODUCTIVITY OF THE FORMATION IN WELLS June 9, 1936.

Filed July 5, 1955 3 Sheets-Sheet -1 June 9, 1936. .A L.. ARMI-:VNTRouT Er A1. 2,043,225 METHOD AND APPARATUS FOR TESTING THE PRODUCTIVITY OF THE FORMATION IN WELLS Filed July 5, 1955 5 sheets-sheet 2 2nd/V B. HALL June 9, 1936.

A. l.. ARMENTROUTET A| METHOD AND APPARATUS FOR TESTING THE PRODUCTIVITY OF THE FORMATION IN WELLS Filed Ju/ly 5, 11.955

s sheds-sheet 5 Eef/"Q4 orne] n e, Y

Patented June 9, 1936 UNITED STATES METHOD AND APPARATUS FOR, TESTING THE PRODUCTIVITY OF THE FORMATION IN WELLS Arthur L. Armentrout, Bakersfield, and I Elwin B. Hall, Los Angeles, Calif.

Application July 5, 1935, Serial No. 29,988

19 Claims.

This invention relates to a method and apparatus useful in connection with the drilling and producing of wells and relates more particularly to a method andapparatus for testing the productivity ofthe earth formations encountered in the drilling of oil and gas Wells. A general object of this invention is to provide a rapid, dependable method for accurately determining the productivity of the formation encountered in a Well and to provide a simple, practical `and inexpensive apparatus for carrying out said method.

In the drilling of oil wells and gas Wells it is highly important to determine the productivity of the earth formations encountered as the drilling progresses. In the rotary method of Well drilling, rotary mud or circulation fluid is-pumped through the drilling string into the Well. Formerly, the drillers observed the circulation fluid discharging from the' Well during drilling for vtraces of oil and gas and when such traces were present and indicated favorable producing conditions the drilling string was withdrawn from the well and a screen pipe or liner was cemented in the well to allow the oil or gas bearing sands to produce through an oil tube or producing tube. In a great many instances the sands or formation thus located did not produce in paying volume 4which would necessitate the removal of the cemented-in liner before the drilling could be resumed. In recent years it has been the usual practice to employ core drills to obtain samples or cores'of the earth formation from time to time as the drilling of the Well progresses. When the cores obtained indicate the presence of a productive sand it is usual to employ what is known as a well tester to determine more accurately the productivity of the formation before cementing in the liner or before continuing the drilling. The well testers just mentioned are often very eX- pensive of manufacture and operation. Further, much difficulty, expense and -delay has attended the use of well testers because they very often become caught or stuck fast in the well due to their operation by a weight or go-devil dropped into the well to actuate their valves,4 packers, etc. and due to other conditions. As the Well testers that are in general use are fabricated of steel or other metal they must be shed from the well at great expensevwhen they are thus caught and and in instances where they cannot be fished out the Well must be abandoned or side-tracked past the lost tester.

Another object of the present invention is to provide a commercially practical method for testing the productivity of the formation in a well (Cl. 16S-1) that does not endanger or imperil the well or cause excessive delay as it cannot under any conditions necessitate a fishing operation.

Another object of this invention is to provide a simple, effective method for testing the produc- 5 tivity of a selected zone or stratum in a Well to accurately determine the character and quantity of the fluid produced by the selected zone or stratum.

Another object of this invention is to provide l .a method for testing the productivity of the formation in a well bore that does not necessitate the lowering of complicated testing devices into the Well or the setting of metal tools in the well that are liable to become immovably xed or l stuck.

o Another object of the invention is to provide a. method for determining the productivity of the formation in a Well that requires a minimum number of simple operations. f

Another object of the invention is to provide an apparatus or device for testing the productivity of the formation in a well that does not in any instance require removal from the well following the completion of the test and, therefore, never necessitates a fishing operation.

Another object of this invention is to provide an apparatus or tester for testing the produc- Y tivity of the formation in a well that is formed entirely of parts and material that may be readily broken up or drilled up following the completion of the test to permit the drilling of the well to progress or to permit the setting of an oil string and its liner as the particular case may require. The apparatus or tester of the present invention may be fabricated of inexpensive friable material so that it may be easily broken up by drilling tools following the completion of the test and the material of which it is formed carried from the well by the usual circulation fluid.

Another object of the invention is toprovide an apparatus or tester for testing the formation in a well that is operable to obtain a normal, uncontaminated and fully representative test of the fluids produced from the selected stratum in the Well.

Another object of this invention is `to provide an apparatus or well tester of the character mentioned that embodies an effective packing means for excluding the liquid and the hydrostatic pres' 50 ysures of the liquid in the well from the sands or formation being tested.

The various other objects and features of the invention will be fully understood from the following detailed description of typical manners of carrying out the method and typical forms of the invention, throughout which description reference is had to the accompanying drawings, in which: p

Fig. 1 is a partial side elevation and partial vertical sectional view of one embodiment of the invention in position in a well, illustrating the manner in which the cement is conducted to the cement basket. Fig. 2 is a view similar to Fig. 1 showing the frangible sealing disc removed or brokenaway to permit the fluids from the formation being tested to fiow into the test string. Fig. 3 is a fragmentary vertical sectional view of the lower portion of a well having a casing cemented therein illustrating another embodiment of the invention'with a portion broken away to appear in vertical cross section and illustrating another manner of carrying out the method. Fig. 4 is a vertical sectional View of the lower portion of a well having a pilot bore or rat hole illustrating another form of the invention arranged in position to make a test in accordance with another manner of carrying out the method with a portion broken away to appear in vertical cross section. Fig. 5 is a vertical detailed sectional view of still another embodiment of the apparatus positioned in the well with its packer in the unactuated condition and Fig. 6 is a view similar to Fig. 5 showing the packer actuated.

. Thepresent invention is adapted to be embodied in various forms and in forms for use in various situations. In the following detailed disclosure we will describe several typical embodiments ofthe invention and will follow such disclosures with descriptions of the method as carried out in the operation of these particular embodiments of the apparatus. It is to be understood that the invention is not to be construed as limited or restricted to the specific details set forth but that it is to be taken as including any features or modifications that may fall within the scope of the claims.

The form or embodiment of the apparatus illustrated in Figs. 1 and 2 of the drawings includes, generally, a. friable o-r frangible body I0 having a perforate lower portion II, a string of pipe or tubing I2 releasably connected with the body IU, a frangible closure disc I3 initially sealing off the interior of the perforate lower portion II of the body from the upper portion of the body, and a cement basket I4 on the body I0 for receiving cement to seal of the liquid in the well B from the formation being tested.

The body I0 is an elongate member and is tubular or preferably tubular throughout the major portion of its length. The body I 0 is adapted to be run into the well bore B on the string I2 to a position where its perforate' lower portion I I is inthe zone of or is within the stratum S to invention that the body I0 is frangible or vfriable so that it may be readily crushed or broken up by drilling tools or the like. It is to be understood that the bodyIll is sufficiently strong to be lowered its proper position in the well without fracturing or -failing and is adapted to withstand the flow and pressure conditions In the well. The invention contemplates the constructing or forming of the body I0 of cement or other cementitious materials or combinations of the samefbakelite, glass, hard rubber compo- 5 sitions or any other material that may be easily broken up or crushed by drilling tools or other tools run into the well for that purpose.

The body IIJ is preferably integral, it being understood, of course, that it may be made up 10 of a plurality of sections if desired or necessary. The perforated lower portion II of the body I Il operates as a liner or screen during the test admitting the fluids from the stratum S to the longitudinal opening I5 of the body. In the par- 15 ticular case illustrated in the drawings, the portion I I is provided with a multiplicity of vertically spaced and circumferentially spaced slots I6 and substantially cylindrical openings II which extend outwardly from the opening I5 to the pe- 20 riphery of the body.- 'I'he length of the perforated portion I I of the body depends upon the vertical extent of the exposed stratum S being tested, it being understood that the portion II may be of any desired length. 254

The string I2 of pipe or tubing is provided primarily to lower or carry the body I0 to the desired position in the well bore B and to conduct the sample or test fluid to the surface of the well. The string I2 performs other functions as 30 will be hereinafter described. The test string I2 is made up of a plurality of lengths of casing, pipe or tubing in the usual manner. In accordance with the invention the string I2 is releasab'ly connected with the body I0 to be easily detached 35 therefrom following the completion of the test. The invention contemplates the connection of the string I2 with the body I0 by a releasable coupling, a safety joint or other readily releasable device. In the particular case illustrated in the drawings the lower end portion of the string I2 is releasably connected with the body I0 by left hand threads I8. The lower end part of the string I2 is preferably threaded into the upper end portion of the tubular body I0. I'he left 45 hand threads I8 may be easily unthreaded or disconnected without loosening the right hand threaded joints of the string I2. The upper end I9 of the body l0 is preferably inclined downwardly and inwardly. 50

'I'he frangible closure disc I3 extends across and closes off the opening I5 of the body above the slots I6 and perforations I1. The disc I3 is provided to exclude the cement from the perforated body portion II when the cement is introduced 55 into the basket I4. The disc I3 also acts to exclude liquid in the well from the upper portion of the body III and the string I2 when the string is run into the well so that the string may be floated into the well with the interior of the 60 string I 2 and the upper portion of the body opening I5 dry or substantially dry. The disc I3 is frangible so that it may be readily broken out by a tool or tools run in through the'string I2 and may be formed of cast metal, cementitious 65 material, ceramic material, glass, bakelite or any other impervious material that is readily fractured and broken. The peripheral edge portions of the disc I3 are received in an annular groove or recess 20 in the wall of the opening I5 and may 70 be molded or cast directly in the body.

'I'he basket Il is attached to and surrounds the body I0 above the'multiplicity of slots IB and openings II and is adapted to receive cement C which is introduced into the well bore B above 75 amazes lis .secured to the body I0 by a band 2I while its upper end is open to the well bore. The basket I4 is adapted to expand and bear outwardly against the wall of the bore B when it receives the cement C. Openings or ports 22 are provided in the wall of the body I0 above the disc I3 to conduct the cement C from the body opening I5 to the interior of the basket I4. Check valves 23, while lnot essential, may be provided atthe ports 22. The valves 23 illustrated in the drawings consist of flexible arms or straps whose lower ends are secured under the band 2|. 'I'he straps constituting the valves 23 extend upwardly from under the band 2I- to normally cover and close the ports 22. When the body Ill is run into the well on the string I2 the valves 23 are held in their closed position by `the hydrostatic pressures in the well and exclude the liquids in the well from the upper portion of the body opening I5. The valves 23 in being flexible, flex outwardly to their open positions when the cement C is passed or forced outwardly through the ports 22. rllhe strap 2l and the valves 23 may be formed of any suitable material and if found necessary or desirable may be formed of `metal asthey are so small that they do not interfere with the drilling up of the tester following the completion of the test.

The method of the present invention as practiced with the apparatus illustrated in Figs. 1 and 2 is as follows: Assuming `*that it has been learned that the stratum S is an oil bearing sand and assuming that the drilling tools have been removed fromthe Well, the body I0 is attached to the lower end of the test string I2 by the threads I3 andis run into the well on the string. The tester body I0 may be run to a position where its lower end rests on the bottom of the well bore. If desired or found practical, the test string I2 may be run in to the well dry, the disc I3 and the valves 23 operating to exclude the well liquid from the string. It is to be understood that the test string I2 may be run into the well wet or open to the well bore. Following the positioning of the body I0 in the well, cement is passed or delivered to the upper portion of the body opening I5 and the basket I4. 'I'he quantity of cement required to lill the basket I4 and surround the upper portion of the body III for a suilicient distance to dependably exclude the well liquid'from the stratum .S may be readily determined in the well known manner. The cement C may be carried, forced or delivered to the body opening I5 and the basket I4 in any of the well known manners; for example, it may be delivered to the basket bythe Perkins method or may be lowered through the string I2 in a drop bottom bailer to the disc I3 and then put under pressureA to flow through the ports I2 into the well l bore B above the basket I4. It is preferred to employ a quick setting cement so that the body of cement C in the basket and surrounding the body I0 may set in a short time. After the cement C has set the small amount of cement remaining in the string I2 may be drilled out by standard orrotary tools. In the event that there is liquid in the test string following the cementing operation, this liquid may be removed in a suitable manner, as by baillng or pumping. If desired, however, the liquid may be allowed to remain in the test string I2.

Following thecementing operation the method provides for the breaking of the frangible disc I3. The disc VI3 may be readily'broken by cable tools run through the string I2 on a line.` Following the breaking of the disc I3 thev fluids inthel stratum S may now through the slots I6 and openings Il to pass into the body opening I5 and the string -I2. If liquid remains in the string I2 as setl forthabove the fluids freed from the stratum S will displace the liquid from the string, it being apparent that it is preferred to remove the liquid from, the string so that the stratum S may produce under substantially normal pressures and so that the test uid is uncontaminated. In the event that the stratum S does not produce in suiiilcient volumeor at a sufficient pressure to flow out through the string I2 the test yfluids produced into the body I0 and the string I2 may be bailed out, pumped out or removed inv S, allowing the stratum to produce under normal pressures.

lf the test discloses that the stratum S produces the desired fluid in a paying volume, the string I2 and the body I0 may be allowed to remain as shown in Figs. 1.and 2 so that the well may produce through the string. It is usually' preferred, however, to employ a more permanent and effective screen pipe or liner for the production of the well. When it is desired to set a regular or permanent liner the string I2 is first detached from the body I0. This is easily accomplished by rotating the string I2 in a direction to unthread or release the threads I8. The string I2 may then be pulled from the well. Following the removal of the string I2 from the well, the body l0 of the tester and the cement C are crushed and drilled up by suitable tools such as typical drilling tools. 'Ihe body I0 being formed of frangi'ble or friable material is easily drilled up in this manner. The material of which the body I0 and its associated parts are formed may be washed or carried from the well by the circulation fluid leaving the well free for the setting of the liner and oil tubing.

When the test carried out as described above, discloses that thestratum S does not produce the desired fluid in paying quantities the string I2 is detached from the body I0 and pulled from the Well. l'The body I0 and the cement C are then drilled up by suitable drilling tools and the material of which they are formed washed or flushed away. The drilling tool employed to drill up the tester may be employed to continue the drilling of the Well to a greater depth. It will be noted that the method for testing the formation as just described is adapted to accuwell do not requirathe repeated assembling, run,

ning in andpulling out of a string of pipe.

Fig. 3 of the drawings illustrates another form of apparatus and another manner of carrying out the method of the present invention. As shown in Fig. 3 a water bearing sand or stratum W is located 'above an oil or gas bearing stratum O at the bottom of the well bore. In accordance with the manner of carrying out the invention disclosed in Fig. 3, a casing 25 is run`into the well and its lower end or shoe 26 is cemented in the well below the water bearing'stratum W by a body of cement 2'|. This cementing operation may be performed by any of the well known cementing methods. The cement 21 and the casing 25 exclude all water from the well and allow the casing 25 and the open lower portion of the well bore to be bailed free of liquid. A liner or tester body 28 is run into the well on a string of pipe, tubing or casing, not shown,

to a position where it rests on the bottom of the well bore. 'Ihe body 28 is preferably run into the well and positioned before the liquid is bailed or removed from the well.

The body 2B may be substantially identical with the above-described body ||l being friable or frangible and formed of cement, bakelite, glass, or the like. 'I'he lower portion of the body 28 is perforate, being provided with spaced perforations 29 for admitting iluids from the lower open portion of the well bore to the longitudinal body opening 38. The upper portion of the body is imperforate and the body 28 is proportioned so that its upper portion extends into the lower end of the casing 25. The body 28 is adapted to t the casing 28 and the open lower portion of the well bore with suitable clearance. Following the bailing or removal or" the liquid from the casing 25 and the lower portion of the well bore the iluids in the stratum O may freely iiow from the stratum into the body opening 30 and pass upwardly from the body into the casing 25. The body 28 acts as a liner to prevent caving and excessive sanding up of the lower open portion of the well bore. The test fluid which flows into the body opening 30 and the casing 2 5 may be removed from the well by pumping or bailing or may be permitted to ow out through the casing if it is produced under suiiicient pressure. In this manner the stratum O is tested for its productivity. Following the completion of the test, drilling tools are run into the well through the casing 25 and are operated to drill up the body 28 and the drilling operation may be continued with the same tools to deepen the well bore.

Fig. 4 of the drawing illustrates the invention employed in testing the formation -in a well bore having a pilot bore or rat hole R. The rat hole R extends into an oil or gas bearing stratum A and terminates at its upper end in an upwardly facing annular shoulder 36a. The apparatus of the invention employed for testing the stratum A comprises a frangible or friable body 3| and a test string 32.

The tester body 3| is an elongate tubular member formed of cement, bakelite, glass rubber composition, or other material that may be readily crushed and drilled up by well drilling tools. 'I'he major lower portion 33 of the body 3| is adapted to extend into the rat hole R with suitable clearance and is provided with a multiplicity of vertically and circumferentially spaced perforations 34. In accordance with this form of the invention the upper portion vof the body 3| is thickened and provided with a downwardly and inwardly tapered face or shoulder 35. The tapered shoulder 35 is designed to nt on the shoulder 30 of the earth formation. The test string 32 may be made up of a plurality of connected lengths of pipe casing or tubing. The test string 32 is releasably connected with the body 3| by a releasable coupling, a safety joint or by threads 36 as shown in the drawings. The threads 36 are preferably left hand threads so that the string 32 may be easily disengaged from the body 3| without loosening the threaded connections of the string.

In carrying out the method of the present invention with the apparatus shown in Fig. 4 the tester body 3| is attached to the lower end of the string 32 and is run into the well on the lower end ofthe string. The body 3| is run into a position where its inclined shoulder 35 rests on the shoulder 30 and the weight or a portion of the weight of the string 32 is allowed to bear on the body 3| so that the shoulder 35fis held in tight sealing contact with the formation at the shoulder 30. The liquid in the test strlng^32 may then be removed in any of the well known manners to permit the iiuid from the stratum A to flow into the body 3| and the test string 32. The shoulder 35 bearing on the shoulder 30 effectively excludes the well liquid and the hydrostatic pressures in the well from the rat hole R, allowing the stratum A to freely produce into the tester and the test string. 'I'he test fluid may be allowed to flow out through the test string 32 or may be bailed or pumped out as conditions may require.

tester body 3| and pulled from the well leaving the body in the well. A suitable drilling tool is then run into the well and operated to crush and drill up the tester body 3|. If desired, the same drilling tool may then be employed to continue the drilling operation and deepen the well. The tester disclosed in Fig. 4 of the drawings is extremely simple and inexpensive and the method employing this form of the invention is very rapid and effective.

Figs. 5 and 6 of the drawings illustrate still another form of the invention and another manner of carrying out the method of the invention. The apparatus illustrated in Figs. 5 and 6 includes, generally, a tubular friable body 4 0, packing means 4| on the body 40 for packing off the stratum D to be tested and a test string 42 for carrying the tester, for operating the packing means 4|, and for conducting away or receiving the test iiuid.

'Ihe body 40 is an elongate tubular member adapted to be positioned in the well bore E to receive iiuid from the stratum D to be tested.

A plurality of circumferentially and vertically spaced perforations 43 is provided in the lower portion of the tubular body 40 to admit fluid from the formation to the longitudinal body opening 44. The body 40 is provided with a tapered intermediate portion having an upwardly and inwardly inclined surface 45. The body 40 has a reduced cylindrical upper portion 46. The tubular body 40 is preferably integral or monolithic and is formed of a material such as cement, bakelite, ,glass or the like to be readily After completion of the test, the -string 32 may be easily disconnected from the crushed and broken up by well drilling tools.

of the well bore E. 'I'he longitudinal opening of the sleeve 41 has a downwardly and outwardly inclined wall 48 for cooperating with the inclined WAsurface 45 of the body 40. The upper end of the/ sleeve 41 is preferably flat and normal and the sleeve 41 is preferably proportioned to initially grip the body 40.

The packing means 4| includes in addition to the sleeve 41 a follower or actuating member 49. The member 49 is tubular and the lower portion of its longitudinal opening 50 slidably or shiftabl'y receives the upper portion 46 of the body. 'I'he member 4| has a fiat normal lower end for bearing on the upper end of the packving sleeve 41. In accordance with the invention the member 49 is connected with the -body 40 I for vlongitudinal movement relative thereto. spaced longitudinal grooves are provided on vals the wall of the opening 50 to receive the projectingI portions of pins 52 on the body portion 46. The pins 52 may be cemented in sockets in the portion 46 or may be otherwise fixed to the body. Openings 53 may be formed in the wallA of the member 49 to permit the attachment of the pins 52 to the body portion 46. The openings 53 may be filled with cement or the like after the attachment of the pins to the body. The member 49 is frangible or friable, being formed of cement, bakelite, glass, hard rubber or theO like to be readily drilled up by Adrilling tools. The string 42 is made up of a plurality of lengths of pipe, casing or tubing. The lower end of thev test string 42 is removably. or de- 5 tachably connected with the member 29. The

string 42 may be connected with the member 49 by a releasable coupler, a safety joint or by means of threads 54 as shown -in the drawings. The threads 54- are preferably left hand threads so that they may be disengaged without loosening the right hand threaded connections of the test string. The test string 42 is threaded inl the upper end of the member 49 to be in communication with the opening 50 and the body opening 44.

operating the device illustrated in Figs. 5 and 6 is as follows: The parts of the tester proper are assembled as shown and the member 49 is connected with the lower end of the. string 42 by the threads 50 so that the tester may be run into the well on the lower end of the test string. The

device is run into the well to a position wherey the lower end of the body 40 rests on the bottom of the well bore. After the apparatus has been positioned, the weight or a portion of the weight of the test string 42 is allowed tov rest or settle on the member 49. The weight thus applied to the member 49 causes' downward movement of the member 49 and the pressure and movement are transmitted to the packing sleeve 41 causing .compression and outward expansion of the sleeve. 'I'he cooperation of the inclined body surface 45 and the inclined internal surface 49 of the sleeve causes the sleeve to spread orexpand outwardly following detachment of the string from the body. The method of the invention as carried out in to tightly seal with the wall of the well bore E.

It will be apparent that the sleeve 41 also has tight sealing contact with the body 40 and the lower end of the member 49. Thus, the packing sleeve 41 seals ofl the Well bore above the stratum 5 D to exclude the well liquid and the lwell pressures from the. stratum.

The liquid present within the test string 42 may be pumped out or bailed out, whereupon the iiuids in the stratum D may freely pass into the body opening 44 through the ports 43 and flow upwardly into the test string 42. Under some conditions the stratum D may produce fluids under sufficient pressure and in suiiicient quantity to flow out through the tubing 42 to the surface. In other instances it may be necessary to withdraw the test iiuid from the string 42 by bailing, pumping or the like. In this manner the formation D is easily and quickly tested for its productivity. Following the completion of the test, the test string 42 is rotated in a. direction to unthread the threads 54 and is withdrawn from the well leaving the tester resting on the bottom of the well. Drilling tools may then be run into the well to drill up the tester and continue the drilling operations, if this is necessary. The body 40 and the member 49 are formed of material that is readily crushed or broken up by the drilling tools while the rubber'sleeve 49 is quickly destroyed when the tester is crushed and drilled 30 up by'the drill or drilling tools. The form of the apparatus illustrated in Figs. 5 and 6 of the drawings is operable to dependably seal oi` the portion of the well to Abe tested and is simple to operate. Further, the device is inexpensive of manufacture and may be employed without endangering the well.

Having described only typical forms and applications of our invention, We do not wish to be limited or restricted to the specic forms and. applications herein set forth, but wish to reserve to ourselves any modifications or variations that may appear to those skilledV in the art or fall within the scope of the following claims.

Having described our invention, we claim:

1. Apparatus for testing the formation in a well including a tubular string adapted to be run into the well, a body releasably connected with the lower end of the string and having an opening I communicating with the string and perforations 50 for carrying the test fluid to the opening, and means on the body for excluding the well liquid from the stratum tested, said body and means being friable to be drilled up by drilling tools 2. Apparatus for testing the formation in a well including a tubular string adapted to be run into the well, a friable body having a longitudinal opening and lateral perforations for con- Y. ducting the test fluid to the opening, and means connecting the body to the string with its opening in communication with the string, and releasable to permit withdrawal of the string from the well whereupon the body may be drilled up to leave the well clear for further operations.

3. Apparatus for testing the formation in a well including a friable tubular perforate body, a string adapted to be run into the well, and means for connecting the body with the lower end of the string to be run into the well thereon, said means 7o being releasable to permit the withdrawal of the string from the well without .the body so that the body may be drilled up to leave the well clear for other operations. A

4. Apparatus for testing the formation in a 75 well boreV including a string to be run into the well, a tubular friable body having a lower portion with perforations to receive fluid from the stratum to be tested, means-carried by thebody 5 for closing off the well above said perforations, and means for connecting the body with the string to be run into the well thereon and releasable to permit withdrawal of the string from the well without the body, leaving the friable 10 body therein to be drilled up.

5. Apparatus for testing the formation in a well including a tubular string adapted to be run into the well, a tubular friable body having perforations in its lower portion to receive fluid l5 from the formation to be tested, a cement'basket on the body above the perforations to receive cement for closing oif the well above the perforations, and means connecting the body with the lower end of the string'and releasable to permit 20 Withdrawal of the string from the well without the body so that the body and said cement may be drilled up to leave the well clear after the test.

6. A well tester to be runinto the well on a string to obtain fluid from a selected stratum 25 including a tubular friable body adapted to be connected with the lower end of the string and positioned at said stratum, there being perforations in the body to receive the fluids from'said stratum, the body being adapted to remain in 30 the well following the withdrawal of the string and being adapted to be drilled up to leave the well clear for other operations.

- 7. Afwell tester to be run into the well on astring to obtain fluid. from a selected stratum 35 including a tubular friable body adapted to be connected with the lower end of the string and positioned at said stratum, there being perforations in the body to receive the fluids from said stratum, means on the body for closing off the 40 well above the perforations to exclude the well liquids from said stratum, the body with said means being adapted to remain in the well fol' lowing the withdrawal of the string and beingadapted to be drilled up to leave the well clear 45 for further operations.

8. A well tester to be run into the well on a string to obtain fluid from a selected stratum including a friable body adapted to be connected with the lower` end of the string and positioned 50 at said stratum, there being perforations in the body to receive the fluids from said stratum, a cement basket on the body for receiving cementI for closing oiiE the well above the perforations to exclude the well liquids from said stratum, the 55 cement and the body being adapted to remain in the well following the withdrawal of the string and being adapted to be drilled up to leave the Well clear for other operations.

9. A well tester to be run into' the well on a string to obtain fluid from a selected stratum including a tubular friable body adapted to be connected with the lower end of the string and positioned at said stratum, there being perforations in the body to receive the fluids from said stratum, a packingsleeve on the body expansible .to close oil the well above the perforations to exclude the well liquids from said stratum, the body and sleeve being adapted to remain in the well following the withdrawal of the string and 70 being adapted to be drilled up to leave the well clear for further operations.

10. A well tester to be run into the well on a string to obtain fluid from a selected stratum including a tubular friable body adapted to4 be 'lrgnnecxed with the lower end oi the string and positioned at said stratum, there being perforations in the body tol receive the iluids from said stratum, a shoulder on the body adapted to seat on a shoulder of the formation above said stra- -tum to exclude the well liquids therefrom, the 5 body being adapted to remain in the well following the Withdrawal of the string and being adapted to be drilled up to leave the well clear for other operations.

411. A well tester to be run into the well on a string to obtain iluid from a selected stratum including a tubular friable body adapted to be connected with the lower end of the string and positioned at said stratum, there being perforations in the body to receive the fluids from said l5 stratum, a frangible seal initially closing oil. the interior of the body above the perforations, and a cement basket on the body, there being a port in the body above the seal to pass cement to the basket to close off the well above the stratum, the seal being adapted to be broken after the setting of the cement to admit the test fluids to the string, the body and cement being adapted to remain in the well after the removal of the string and being adapted to be drilled up to leave the well clear. K

12. A well tester to be run into the well on a string to obtain iiuid from a selected stratum including a tubular friable body adapted to be connected with the lower end of the string and positioned at said stratum, there being perfora tions in the body to receive the fluids from said stratum, an expansible sleeve on the body above the perforations, and a friable member on the body movable to expand the sleeve to close oif the well above the perforations to exclude the well liquids from the said stratum, the sleeve, the member and the body being adapted to remain in the well following the withdrawal of the string and being adapted to be drilled up to leave the well clear for other operations.

13. The method of testing the formation in a well including the positioning of a friable tubular member in the well to receive the fluids from a selected stratum by lowering the same into a well on a tubular string, removing the said fluids from the member and string for the purpose of the test, disconnecting the string from the member, removing the string from the well, and then drilling up the member to leave the well clear for further operations.

14. The method of testing the formation in a well including the positioning of a friable perforate tubular member in the well to receive the fluids from a, selected stratum by lowering the same into the well on a string, removing the said iiuids from the string for the purpose of the test, disconnecting the string from the member, removing the string from the well, and then crushing the member to leave the well clear for further operations.

15. The method of testing the formation in a well including the positioning of a friable perforate tubular member in the well to receive the fluids from a selected stratum, sealing oil the well liquids from said stratum to allow the stratum to produce into the member, withdrawing the said fluids from the member for the purpose of the test, and then drilling up the member to leave the well clear for further operations. 16. The method of testing the formation in a well including the positioning of a iriable per -forate tubular member in the well to' receive the fluids from a selected stratum, cementing the member in the well at a. point above the said 2,043,225 stratum, removing the iiuids from the member for the purpose of the test, and then drilling up the member and cement to leave the well clear for further. operations.

17. The method of testing the formation in a well including the positioning of a friable tubular member having a perforate portion in the well to receive the fluids from a selected stratum by running the member into the well on a tubular string, removing the said iiuids from the l member through the string for the purpose of the test, disconnecting the string from the member, removing the string from the well,` and then drilling up the member to leave the well clear for further operations.

18. The method of testing the formation in a well including the positioning of a friable tubular member having a perforate portion in the Well to receive the fiuids from a selected stratum by running the member into the Well on a tubular string, closing off the well around said member to exclude the Well liquids from said stratum,

removing the said fiuids from the member through the string for the purpose of the test,

disconnecting the string from the member, removing the string from the well, and then drilling up the member to leave the well clear for further operations.

19. 'The method of testing the formation in a Well including the positioning of a friable tubular` member having a. perforate portion in the Well to receive the fluids from a selected stratum by running the member into the well on a tubular string, closing off the Well around said member at a point above said stratum by cementing the member in the well, removing the said iuids from the member through the string for the purpose of the test, disconnecting the string 'from the member, removing the string from the well, and then drilling up the member to leave the well clear for further operations.

ARTHUR L. ARMENTROUT. ELWIN B. HALL. 

